Soldering A to Z, Part Three

Firescale Videos (4) by Lexi Erickson, Addie Kidd and Mark Nelson

Minimizing Firescale Tools, Tips and Methods for Cleaning up Bad Solder Joints

Eliminating the Appearance of Views of Diane’s Soldering Bench, Ventilation Firescale System and Studio

Butler’s Finish (Depletion Exercise 8: Line Inlay with 28 Gauge Bezel Guilding)

Electroless Deposition Exercise 9: Soldering Wire to Wire

Super Pickle Exercise 10: Adding a Wire Rim to a Ring Band

Troubleshooting Soldering Problems Fire Scale (also called Fire Stain or %#@!!!):

The gray shadowy color which forms deep into the surface of sterling after heating

– usually looking worse after sanding and polishing.

How it forms: When heated to soldering temperatures, the component in the combines with oxygen molecules and forms two types of oxides.

Pickling will remove the pinkish cuprous oxide that forms on the immediate surface of the sterling silver, but not the cupric oxide that forms deeper into the metal. The deep layers of cupric oxide are harder than the parent sterling silver and are difficult to remove. Image courtesy of Kristin Beeler’s Wordpress Blog for Long Beach College http://art35blog.wordpress.com/

http://art35blog.wordpress.com/ Fire scale is only a problem with sterling silver (and something similar happens to )

Brass, especially red brass, will have a reddish oxide form after heating, but that is easily removed with a special mixture called Super Pickle (a mixture of regular pickle or vinegar and hydrogen peroxide). Preventing (or minimizing) Fire Scale

Create a barrier coating with one of the following:

• White paste flux • Home-made mixture of boric acid and denatured alcohol • Commercial coatings such as Prips Flux, Cupronil, Stop-Ox or Firescoff

or

Create an atmospheric barrier by:

• Using a reducing flame which decrease fire scale by minimizing the amount of oxygen in the flame or

• Working on a charcoal block also decreases the amount of firescale because the burning charcoal forms CO2 and absorbs the oxygen from the vicinity of flame Getting Rid of the Appearance of Fire Scale

The design of the piece can limit which techniques you can use

•Abrasion (filing, grinding, sanding, polishing)

•Electro-Stripping (reverse electro-plating)

•Acid Etching (using a mild nitric or sulphuric solution) •Depletion (“Butler’s Finish” – heat, quench and brush, use detergent and soft brass brush, repeat, repeat, repeat….)

•Plating Most gilding methods are additive, but depletion gilding of sterling silver is actually a subtractive process in which the copper is leached out of the surface of the silver alloy with pickle or acid. The result is a whiter, more even coloration.

Essentially, depletion gilding produces a higher-purity surface by removing everything that is not silver. Things needed for Butler’s Finish (depletion guilding):

•Hot Pickle •Liquid Detergeant •Soft Brass Brush Why does sterling silver turn copper-colored in pickle contaminated by steel?

When pickle turns blue, it means it is full of free-floating copper ions -- very fine, dissolved copper particles which have been leached out of your copper, sterling silver and brass objects when you pickle them. If iron or steel (not stainless) is introduced into the blue pickle solution a natural electrical current is formed and the solution becomes conductive. The pickle solution becomes the electrolyte (plating solution), and your silver object becomes the negatively-charged cathode. The positively-charged copper ions become attracted to the cathode and deposit themselves on its surface. This natural process is called electroless deposition. Electroless deposition does not require an outside electrical source. Instead, it involves two metals that already have the electrochemical potential to induce a natural type of electroplating within a solution.

Of the two metals, one must have the electrical potential to oxidize (lose electrons) and the other to reduce (gain electrons). The oxidation and reduction acts like the negative and positive electrical current; the reducing metal affects the metal ions in the plating solution (in this case the pickle) to cause a layer of metal to form on the oxidizing metal. • If the pickle is accidentally contaminated with steel, you can strip the “flash- plated” copper from your sterling silver by soaking it briefly in a mixture of equal parts pickle solution from the pickle pot and hydrogen peroxide from the drug store.

• (Note: This also works to remove the pink color that develops on brass after heating) Super Pickle Aproximately Equal parts of:

•H2O •Vinegar (or fresh pickle from the pickle pot) •Hydrogen peroxide (Eliminate the water if you want a stronger solution) Trouble-Shooting Common Soldering Problems Trouble-Shooting Common Soldering Problems

Solder won’t flow • Not enough heat – wrong kind of torch, wrong kind of torch tip, or flame not hot enough • You are giving up before object reaches soldering temperature • Heat sinks interfering - (such as tweezers, third arms, screen, etc.) robbing heat away from parts being soldered; • Too much heat dissipating away from the object being soldered – soldering large object in the open without insulating arrangement of firebrick to reflect heat back Solder and metal parts turn black and solder won’t flow • Prolonged heating resulting in flux burning away before solder melts Pitting in the joint/seam (solder erosion) • Metal and solder overheated, or • Not enough flux or flux burned off, or • Zinc burned out of the solder alloy Sunken looking seam • Not enough solder Are the Parts and the Solder Clean? Did you pickle between solderings?

Important: Pickle removes fire scale, hardened flux, finger-prints, correction fluid and other gunk. Pickle works fastest if used hot. Rinse with tap water after pickling.

Don’t forget the solder should be clean also! Was the joint tight? Was it light tight?

Did you use enough flux? Did you use the right type of flux?

Did you heat the work fast enough and was it evenly heated by the time the solder flowed? When you placed the solder on the joint, did it touch both sides of the joints?

Solder is attracted first by capillary action and direction of the heat, and second to gravity.

If the solder is not touching both parts of the joint, when it liquefies, it will pool or run instead of flowing into/along the joint. Lexi Erickson Soldering Wire to Sheet

http://www.youtube.com/watch?v=_J2wZHLG qO0&feature=related

2 minutes, 26 seconds Addie Kidd Video for Art Jewelry Magazine: Soldering a Bezel Part 1

http://www.youtube.com/watch?v=M3gG- lX70eA&feature=related

4 minutes, 32 seconds Addie Kidd Video for Art Jewelry Magazine: Soldering a Bezel Part 2

http://www.youtube.com/watch?v=dSjFYUj0v HQ&feature=related

8 minutes, 36 seconds Rio Grande Video Soldering Jump Rings in a Chain

http://www.youtube.com/watch?v=E1FRHT9jz WQ&feature=related

9 minutes, 42 seconds; Or start Video at 3:40 to see the most important part Less-Than-Desirable Soldering Outcomes?

As hard as you try, there still seems to always be clean up to do!

Options for Clean Up:

Traditional Choices: Files, sandpaper and emery cloth, scrapers, elbow grease Modern Tools:

Flex shaft or MicroMotor tool, and accessories such as sanding discs, sanding drums, rubber abrasive wheels and cones, silicone radial wheels, diamond burrs, rotary burrs and hi-tech sanding papers •First remove any lumps or blobs with a file, scraper or burr

•Riffler files have curved tips and can get into places regular needle files can’t

•Next smooth the area with sandpaper, radial disc or rubber abrasive wheels and/or cones

•Final finish can be satin or polished – steel wool, brass brush or buffing wheel

Be careful not to file, scrape or abrade deep divots or valleys in the metal surfaces

When using rotary tools and abrasive discs and cones, keep the tool moving evenly across the surface Think carefully about where you place your solder. Try to place the solder in areas that will be easy to access with files, burrs or sandpaper in case you are left with a solder ghost or puddle. Always postpone excess solder clean-up when both of these circumstances are present: •There is not a chance of the excess solder running further or penetrating further into the primary parts being joined

•You will be able to access the solder later to do the necessary clean-up But do clean up solder blobs and spills (where solder has flowed outside the seam) before they diffuse further into the metal surrounding the solder seam. Reason: To avoid seam shrinkage or burn out in subsequent soldering operations

Correction fluid is a good idea as well The difference in hardness between the solder and the work piece is often evident after polishing. The solder polishes at either a faster or slower rate than the rest of the piece (depending on the type of solder used) with the result being either a ridge or a valley in the solder joint. The tighter your joining (i.e., the narrower the gap), the less pronounced the defect. Similarly, solder will often etch at a different rate than the materials it is joining. With copper etched in Ferric Chloride for example, the solder remains raised as the copper etches and dissolves away. This leaves a raised solder seam which can be quite decorative !

Cutting Tools: Files, rotary burrs, scrapers Abrasives: Sanding sticks, rubber abrasive cones and discs, sanding drums, radial discs, Mylar-backed sanding film Diamond-coated Tools: burrs, discs, drums Tray of Abrasive Tools For Use in Flex Shaft Careful: Mounted silicone cones and drums have a steel point that will become exposed as the rubber wears away Flex Shafts and Micro Motor Sandblasting Cabinet

Exercise 8 - Alternative T-Joint (Line Inlay with 28 Gauge Bezel) Using your rectangular piece of 20 gauge copper, cut a 1.25” slot (can be slightly curved) with a #1 saw blade

Insert your piece of fine silver bezel into the slot so that it follows the full length of the slot

Solder with Medium-Hard solder using solder balls and the conduction soldering method (support work on tripod and screen and heat from below) Exercise 8 Line Inlay With Bezel Wire

Sheet Metal Thickness: Saw Blade Size:

28 gauge = #1 Blade (.0126”) 26 gauge = #5 Blade (.0159”) 24 gauge = #8 Blade (.020”) Exercise 9 Soldering Wire to Wire

Using the 12 gauge red-brass wire in your metal kit, create a simple knot or twist design in which the wire overlaps itself at least three times

Notch each intersection where the wire overlaps and solder Exercise 9 Or, better yet….. Design your initials in 12 gauge wire

Notch and file wires appropriately where they overlap, abutt or angle into one another. dyf DYF Exercise 10 : Adding A Wire Rim To A Ring Band Exercise 10 :

End Part Four